The kinetic mechanism of the unidirectional H2-oxidizing hydrogenase from soybean nodule bacteroids has been investigated with highly purified enzyme. Measurements of the Km for H2 vary from 0.97 to 2.6 microM, and the Km for methylene blue varies from 6 to 17 microM. With H2 and methylene blue as substrates, the initial velocity patterns are intersecting. High levels of methylene blue are inhi...

cADP-ribose, which is produced by ecto-ADP-ribosyl cyclase of CD38 or bone marrow stromal cell antigen-1 (BST-1), is a key regulator of Ca2+-induced calcium release in an Ins(1,4,5)P3-independent manner. In the present study, we have identified a specific peptide inhibitor for ADP-ribosyl cyclase of BST-1. A 15-mer random peptide phage library was screened with a soluble form of BST-1 expressed...

The degree of inhibition of rat intestinal alkaline phosphatase by L-phenylalanine was highly pa-dependent and varied from 0 to 66% within a pH range of ‘7.8 to 10.4, exhibiting a peak at pH 9.2 and 8.7 for phenylphosphate and /3glycerophosphate, respectively. Vm,, was also a function of pH with and without the inhibitor. Rat intestinal alkaline phosphatase exhibited maximum enzyme activity at ...

The degree of inhibition of rat intestinal alkaline phosphatase by L-phenylalanine was highly pa-dependent and varied from 0 to 66% within a pH range of ‘7.8 to 10.4, exhibiting a peak at pH 9.2 and 8.7 for phenylphosphate and /3glycerophosphate, respectively. Vm,, was also a function of pH with and without the inhibitor. Rat intestinal alkaline phosphatase exhibited maximum enzyme activity at ...

Sodium salts of four n-alkyl xanthate compounds, C2H5OCS2Na (I), C3H7OCS2Na (II), C4H9OCS2Na (III), and C6H13OCS2Na (IV) were synthesized and examined for inhibition of both cresolase and catecholase activities of mushroom tyrosinase (MT) in 10 mM sodium phosphate buffer, pH 6.8, at 293 K using UV spectrophotometry. 4-[(4-Methylbenzo)azo]-1,2-benzendiol (MeBACat) and 4-[(4-methylphenyl)azo]-phe...

If the final position of a team is already secured independently outcomes remaining games in round-robin tournament, it might play with little enthusiasm. This detrimental to attendance and can inspire collusion match-fixing. We demonstrate that tie-breaking rules affect occurrence such situation. Its probability quantified via simulations for four groups 2022/23 UEFA Nations League A under two...

The kinetic mechanism of phosphofructokinase has been determined at pH 8 for native enzyme and pH 6.8 for an enzyme desensitized to allosteric modulation by diethylpyrocarbonate modification. In both cases, the mechanism is predominantly steady state ordered with MgATP binding first in the direction of fructose 6-phosphate (F6P) phosphorylation and rapid equilibrium random in the direction of M...

The interactive inhibitory effects of pH and chloride on the catalysis of laccase from Trametes versicolor were investigated by studying the alteration of inhibition characteristics of sodium chloride at different pHs for the oxidation of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid). At pH 3.0, the addition of sodium chloride (50 mM) brought about a 40-fold increase in Km(app) and a 4...